This invention relates to a fuel-supply system of an internal combustion engine, and more particularly, to a fuel-supply system for extracting fuel vapors and other vapors and rendering them harmless before returning them to the atmosphere.
It is well known that fuel vapors can be problematic in the fuel-supply system for internal combustion engines, especially engines of the two-cycle crankcase-compression type with fuel injectors. Fuel vapors are unpredictable and their concentration in the fuel-supply system varies. The unpredictability of the vapors causes the charge former to run lean or rich, resulting in poor engine performance.
In the past, fuel-vapor separators were installed in the fuel supply to give vapors a chance to come off the liquid fuel so that they were not mixed with the liquid fuel in the fuel discharge running to the charge former. A vent is provided on the separator to remove fuel vapors to the engine or atmosphere. Fuel vapors vented to the engine are mixed with a preexisting air-fuel charge. Although venting the fuel vapors to the engine helped to prevent mixing with the liquid fuel, the solution is temporary because the fuel vapors transferred to the engine interfere with the proper air-fuel ratio in the engine. Venting the fuel vapors directly to the atmosphere is not an acceptable solution because it causes additional harm to the environment.
It is therefore a principal object of this invention to provide an internal combustion engine with a fuel-supply system that removes fuel vapors from the liquid fuel without directly releasing the vapors to the atmosphere and without transferring the vapors to the engine in such a way that the air-to-fuel ratio in engine is affected.
It is a further object of this invention to provide a fuel-vapor reduction arrangement particularly adapted for use with a two cycle internal combustion engine.
Further objects and advantages will be apparent from the ensuing figures and description of the invention.